Milbeaut and EXPEED

A lot of people don't understand the imaging ASICs* that are embedded in their cameras. Canon calls theirs DIGIC, Sony has BIONZ, and Nikon has EXPEED. These special chips are, for the most part, actually customized variations of existing imaging processor chips. In Nikon's case, they use the Fujitsu Milbeaut (as do Leica, Pentax, and Sigma, I believe).

Choice of underlying chip has ramifications on what can and can't be done down the line. For example, Canon's DIGIC can be used in multiples and can execute out of internal memory, which is one reason why you see multi-DIGIC cameras at the high performance end and we have software like Magic Lantern that can execute off an SD card for Canon products. Milbeaut, unfortunately, can't be used in multiples and executes internally.

This past week Fujitsu announced the latest iteration, the seventh-generation MB86S22AA, which gives us some clues about what future Nikon DSLRs might be able to do. Expect an EXPEED4 soon.

First, what is a Milbeaut? Well, it has a dedicated ARM Cortex CPU inside. It also has a DSP (digital signal processor) and modules for demosaicing, image manipulation, compression/decompression, memory management, TV outputs, and card media output.

The new features of the latest Milbeaut tell us something about future possibilities in the Nikon DSLR world. In particular, one specification stood out: 24mp at 12 fps maximum processing speed (the previous version was limited to 14mp at 8 fps, though Nikon seems to have some specialized handling cases in EXPEED variations that exceed that). Still, that new throughput ability sounds remarkably like what a D400 would need, doesn't it? Other published changes include:

New optical correction capabilities.

Faster image processing (double the performance for stills).

Support for Dolby Labs' JPEG-HDR encoder.

New video compression/decompression algorithms for 1080/30P and 1080/60i HD video.

30% lower power consumption.

So how does that all translate into expected new Nikon DSLR/EXPEED changes?

Less power consumption = longer battery life, all else equal.

The faster optical correction capabilities may remove the buffer limitations imposed by Nikon's current Auto Distortion Control setting.

Faster image processing internally coupled with some changes in the RAM and write modules probably means better performance under buffer full situations, and may even stretch buffers slightly on cameras with state-of-the-art cards.

We may see JPEG-HDR introduced as a new capture option.

24mp at 12 fps pushes us forward in terms of top-end burst rate performance capabilities enough to enable the D400 the DX world covets, and may have impacts on cameras with more pixels, such as any D600 or D800 update, or the expected D4x.

Note that Nikon's EXPEED almost certainly isn't a stock Milbeaut, but likely a customized one. Note also that Nikon in 2009 Nikon established a subsidiary jointly owned with Fujitsu which is responsible for all firmware development in Nikon cameras. Thus, the relationship between the two companies is very close, and there's likely cross pollination of ideas between the two in how to evolve the Milbeaut/EXPEED. Quite obviously, much of the firmware in a Nikon DSLR is working through capabilities in the EXPEED chip itself, so I consider it highly likely that the Nikon DSLR firmware group has been working with the new Milbeaut for some time now. We should find out exactly what that means with the next DSLR camera introduction.

* Technically, image processors have moved away from what we usually call ASIC (application-specific integrated circuit). Milbeaut and many of the other image processor chips are probably better called ASSPs (application-specific standard products). Off-the-shelf integrated circuits that perform generalized tasks, like CPUs, would be ISICs (industry-standard integrated circuits). I still call EXPEED an ASIC because while it is based on a standard product (Milbeaut), it appears to be customized for Nikon's specific needs.